\begin{table}[tbp] \centering
\newcolumntype{R}{>{\raggedleft\arraybackslash}X}
\newcolumntype{L}{>{\raggedright\arraybackslash}X}
\newcolumntype{C}{>{\centering\arraybackslash}X}

\begin{tabularx}{\linewidth}{lccc}

\toprule
Election type&Year t&Year t+1&Nb of races \tabularnewline
&(running variable)&(electoral outcomes)& \tabularnewline
&(1)&(2)&(3) \tabularnewline
\midrule &1958&1962&475 \tabularnewline
&1962&1967&337 \tabularnewline
&1967&1968&484 \tabularnewline
&1968&1973&458 \tabularnewline
&1973&1978&481 \tabularnewline
&1978&1981&483 \tabularnewline
&1988&1993&557 \tabularnewline
&1993&1997&560 \tabularnewline
&1997&2002&565 \tabularnewline
&2002&2007&574 \tabularnewline
&2007&2012&221 \tabularnewline
&2012&2017&562 \tabularnewline
\midrule Total&&&5757 \tabularnewline
\bottomrule 

\end{tabularx}
\end{table}
